Attractive and Repulsive Intermolecular Interactions of a Polar Molecule: Short-Range Structure of Neat Supercritical CHF3 Investigated by Raman Spectroscopy

摘要: The short-range structure of the neat fluid fluoroform (CHF3) is investigated around gas−liquid critical point by measurements spontaneous Raman spectra C−F symmetric stretching (ν2) and C−F3 deforming (ν3) modes. are obtained at reduced temperatures 0.96 ≤ Tr = T/Tc 1.06, conditions which permit isothermal studies in gas, liquid, supercritical states as functions pressure and/or density. As density increases, spectral peaks shift toward lower energy side widths become broader. In region, amount shifting shows nonlinear dependence, while width becomes anomalously large. We analyze these dependences along vibrational coordinates perturbed hard-sphere model. decomposed into attractive repulsive components, changes energies evaluated packing fraction, both conti...